Apparatus for dressing grindstones



Aug- 15, 1944 H. c. BARBOUR vET A1.. 2,355,844

n APPARATUS FOR DRESSING GRINDSTONES l Filed June 9, 1943 3 Sheets-Sheetl 4f t I L *F- l 2z 0 umm u-ll-l n mw 2f lI K Y INVENTOR. 56.1 Hon/,4R0C50/Peau@ Aug. 15,1944. H. c. BARBOUR ET A1. 2,355,844

y APPARATUS FOR DRESSING GRINDSTONES l Filed June 9, 1943 SSheets-Sheet2' 52 l r mwummummnnu A v l I v Y. 4 lll L t Hon/,4420 C. 54.9500@ (44BYFRANKL//v 5. M/uE/ www0/HYS Aug. 15, 1944. H. c. BARBOURY ET AL2,355,844

APPARATUS FOR DRESSING GRINDSTONES A Filed June 9, 1945 5 Sheets-Sheet 3HTTOHYW? Patented Aug. 15, 1944 APPARATUS FOR DRESSING GRINDSTONES'Howard C.. Barbour, Elyria, and Franklin s.

Miller, Amherst, Ohio, assignors to The Cleveland Quarries Company,Cleveland, Ohio, a corporation-of Ohio v v Application June9, 1943,Serial No. 490,158

s claims.

'This invention relates to apparatus for dressing the peripheries ofgrindstones s-uch, for example, as the ordinary sandstone'grindstones Lwhich have previously been cut and drilled centrally thereof.

The object of the present invention is to pro- `vi`de apparatus by whichgrindstones can be dressed rapidly and accurately without danger oichipping `or breaking oli portions of the stones at the edges of theannular surfaces being dressed. In other words, it is the principalobject of theiinvention toprovide a method and apparatus by which theoutput of the apparatus can be vastly increased over that of dressingmethods and apparatus heretofore employed.

The invention may be further briey sum- ,.marized as consisting incertain details ofY conf struction and combinations andrarrvangements ofparts which will be described inthe specification and set forth in theappended claims,

In the Vaccompanying sheets of drawings, Fig. 1 is a partialsideelevation and Fig. 2 is a Ypartial plan view of one form of dressingmachine, this machine being adapted for dressing grindstones vof smallersizes;

Fig. 3 is a partial side elevation and Fig. 4 is a partial plan view ofa modified form of dressing machine, this machine being adapted fordressing somewhat larger grindstones;

' Fig. 5 :shows the rough grindstone and the two cuttingdisks at thestart of the dressing opera- 'tion, this view showing disks of the typeillustrated in Figs.`1` and 2;

Fig. 6 is another v iew o f the same near the *completion of thedressing operation;

Fig. 7 is a view showing the completion of the ldressing operation;

the dressing operation under way; and

' Fig. 12 is a view oi the cutting disks of Figs.

" 3 and 4, this view being similar to Fig. 7 and showing the dressingoperation completed.

Referring now to the drawings, I5 represents a portion of the bed of adressing machine similar to a lathe' bed but omitting the supportinglegs Rotatably supported onthe bed is a spindle I6 which is driven by amotor (not shown). This spindle is adapted to rotate the grindstone IIto be dressed. The grindstone I'l is adapted to be secured against ashoulder I8 `on the spindle by a clamping block or flange I9 and-a nut20. By simply removing the nut and slipping oil the clamping block orflange I9, the grindstone can be slid off the spindle, and in similarfashion a new grindstone can be quickly applied to the spindle. Thespindle is adapted to be adjustably supported on the bed by means of apair of Vpillow blocks 2l and 22 movable along ways 23 of the bed.

On a pair of ways 24 and 25 of the bed are two slides 26 and 21` whichare adapted tobe simultaneously moved toward and away from each other bya handwheel28 which is connected by means of a worm 29 shown by dottedlines in Fig. 2 to a righthand and lefthand threaded screw 30 which issupported at the front of the bed. The righthand and lefthand threadedportions of this screw are engaged by nuts carried by extensions 3lsupported by the two slides 26 and 21, see particularly Fig. 1. The twoslides 26 and 21 are provided with undercut ways 32 at right angles tothe longitudinal axis of the machine on which are mounted two slides 33which are movable back and forth with reference to the grindstone I'I bymeans of hand levers 33a.

These slides carry two cutting disks 34 and 35 which are pitcheddownwardly and outwardly as shown in Figs. 1, 2, and 5 to 8 inclusive.The angle of the downward and outward pitch of the cutting disk isimportant both from the standpoint of effective cutting and from thestandpoint of maintaining the disks in sharpened condition. We find thatan angle of not more than 17 and not less than 14 is satisfactory forthis purpose; that is to say, the disks should be pitched downwardly andoutwardly to this eX- tent. In other words, the cutting disks are sosupported that they are pitched outwardly this denite amount and arepitched downwardly the same amount. By reference toFig. 9 it will beseen that the disks 34 and 35 have beveled edges 36 which are beveled tosubstantially the same extent that the disks are pitched downwardly andoutwardly.'

With the apparatus described above, the grindstone is dressed in thefollowing manner:

Assuming that the grindstone I'I with its rough outer periphery which isto be dressed is attached to the spindle I6, the spindle-'is rotated andthe handwheel 28 is turned to mov'e the screw 30 and bring the diskssimultaneously toward each other until their cutting edges engage thegrindstone, whereupon the disks will be rotated by contact with therotating grindstone. The operator continues to turn the handwheel 23bringing the two disks toward each other until a ridge lla (see Fig. 6)is left at the center of the periphery Aof the grindstone. Then one ofthe disks, in this instance the disk 34, is moved laterally from theperiphery of the grindstone -by the operator turning one of the handlevers 33a until the disk is substantially in the position shown in Fig.7, whereupon movement of thescrew 30 is continued, causing the othercutter, in this instance the disk 35, to bemoved in the same directionas before to cut through vthe ridge lla on the grindstone.

In Fig. '7 is shown the grindstone l with its periphery completelydressed, whereas in Fig. is shown the grindstone I1 at the start of thedressing operation. Fig. 6 shows the grindstone partly dressed readytohave the cutter134 backed away from it and .to allowthe other cutter toremove theridge lla. In this mannerchipping of the edge of thegrindstone is avoided as would belikely to occur if a singlecuttingdisk-were employed and the vdisk were moved across the entire peripheryof the grindstone.

Referring now to Figs.l 3 and 4 and Figs. 10, 11 and 12, it will be seenthat invthis instance the dressing machine has a bed 31 which is.provided with a rotatable spindle 38 which is adapted to receive agrindstone 39 whose peripheryis to be dressed, the spindle being motordriven as in the previously described construction. .The bed 3l has ways49 on which is movable a slidedl having undercut ways 42 (see Fig.r3) atright anglesto the longitudinal aXis of the machine and on these lastmentioned ways is adapted to be moved a second slide 43 which can bemoved toward and from the axis of the machine-by rotating a lever 44 toadapt the machine for grindstones of different diameters. 'The slide 4|has an adjustable stop 45 which limits the movement of the slide 43toward the axis-of the-machine.

The slide 43 has a slide '46 which carries two supports -41 and 48 forthe cuttingdisks49 and 50. The supports 4l and 48 can be moved'alongways 5I to adjust the distance between the disks -49and 50 and then areadapted to be clamped-in position. The slide 46 carries a screw52which-can be turned Iby a handwheel 53-to adjustthe'position of thedisks 49 and 50. This screw-52 -hasacontinuous one-way thread whichengages a-nutcarried by the slide 4B.

The cutting disks 49 and 50 Vare'arranged like the cutting disks 34 and35 of the construction rst described, that is `to say,-they haveradownward pitch relativeito the machineand an outward pitch relative .toeachother ofthe same angular amounts as in the rst construction.Likewise, the cutting disks are provided with beveled edges 54 similarto the beveled edge-36 of each of theicutting disks .of the rstdescribed construction. The edge 54 of each of the'disks 49 and 59 isbeveled at an angle .substantially equal to the angle of the downwardand lateral pitch of the cutting disks.

With this construction both disks move simultaneously in the samedirection. The screw is rotated in a direction to lcause oneof the disksto start the dressing operation, in this vinstance the disk `49, .asshown in Fig. l1, and Yafter this rotation of the screw 52 is reversed`by turning the handwheel in the opposite direction, bringing the disk50 into operation so as to complete the dressing operation. If desired,the disk 50 may be moved entirely across the periphery of the grindstoneso as to insure a completely smooth periphery, this being shown in Fig.12. In this manner the likelihood of chipping the edge of the grindstoneis eliminated, asinthe case of the construction shown in`Figs. 1 and 2.

Fig. 10 shows the arrangement with a disk 49 about to start the dressingoperation. Fig. 11

'shows the dressing operation partially completed,

and` Fig. l2 shows it entirely completed.

When the dressing operation is completed and anothergrindstone is to beplaced on the spindle 38, one of .thecutting disks, in this instance thedisk 49, is'backed away with respect to the disk .50 so as to .allow thegrindstone to be placed in position without injuring either disk, andthis is accomplished by mounting the disk 49 (see Figs. 3 and 4) on aslide `55 which is movable `.along undercut ways of the -supportz41-byrotating a .hand lever 56. Then as soonras the grindstone is inposition on the spindlethe cutting .disk A'49 and the slide 55 are movedforward :soiasito position the disk 49 in line with .the disk 59. Or, ifdesired,.both disks can be simultaneously backed away and moved forwardby turning .the `hand lever 44.

It will be understood that thespindle :38 and the grindstone 39 aredriven by Ia motor not shown, and the grindstone is attached -to thespindle as in the rst described-constructiomand that at the beginning`of the dressing operation the rst disk'49 (or the disk 5U) is rotatedbyfits contact with the grindstone, and after the dressing operation issubstantially completed and the direction of the screw 52 is reversed,the cutting '-disk59-`(orlthe diskfllg) is immediately rotated bycontact with the grindstone. Likewise, it will be understood that thecutting disks 49 and 50 are self-sharpening, ras'in the constructionfirst vdescribed.

Thus it will be seenthat the objects of the'invention are attained veryeiectively yby either construction, that is to say, the Ycutting rdiskshave long life and are self-sharpening, andthe machine has a veryhighoutput'so that'the cost of dressing each grindstone 'isreduced to aminimum and at the same time the likelihood of chipping or .breakage ofthe edge of the. grindstone is substantially eliminated.

While we have illustratedtwo .embodiments of the invention, we do notdesirevtobeconned .to the precise details of construction yof theapparatus illustrated and described, -but vaim in our claims to coverall modifications which do-'not involve .a departure from the spirit andthe scope of the invention.

Having thus described our invention,:we claim:

1. In.a Amachine for dressing .grindstones, `a frame having a rotatablespindle yon which a grindstone is adapted to be mounted, and means fordressing the periphery ofthe grindstone comprising a pair of slides onthe frame of themachine carrying a pair of cutting-disks, eachcuttingdisk being vpitched downwardly and outwardly and having aself-sharpening beveled (cutting edge, and means -for simultaneouslyfeeding the disks toward each .other for dressing the majorrportion ofthe periphery of thefgrindstone, and means for backingaway-fromtheperi-phery Aof the grindstone one of the disks .fso'that by continuedfeeding ofthe Yother'disk-in thesame -direction as before theremainderof the periphery of the grindstone can be dressed.

2. In a machine for dressing grindstones, a frame having a rotatablespindle on which a grindstone is adapted to be mounted, and means fordressing the periphery of the grindstone comprising a slide on theframe, a pair of supports on the slide carrying a pair of cutting disks,each cutting disk being pitched downwardly and outwardly with respect tothe horizontal axis of the grindstone, and means for bringing one andthen the other of the disks into contact with the periphery of thegrindstone, each disk having a selfsharpening beveled cutting edge.

3. In a machine for dressing grindstones, a

HOWARD C. BARBOUR. FRANKLIN S. MILLER.

